He has told us that he will defer the piano lessons he needs and the belated German lessons that he covets because he has seen what retirement did to his father. "He retired on his 65th birthday, and one year later he was dead. The worst you can do is put your slippers on..." But the events of the past six weeks tell us that something else is driving Sir Alex Ferguson's desire to work on.

When he retracted his decision to retire nearly a decade ago, Ferguson cited his own realisation, after the penny-pinching era of Martin Edwards, as he saw it, that his board were "prepared to try to become the best club in the world" as the principal reason. The opportunistic £20m bid for Samir Nasri – tabled two to three weeks ago, just as the player went public on his discontent at Arsenal – contributes to the sense that Ferguson considers himself to be back in precisely the same place as 10 years back. Then, Roy Keane was railing against the side's inadequacies and Ferguson went out and spent £47m on Juan Sebastian Veron and Ruud van Nistelrooy, to help create a side which might challenge for the European Cup in his beloved Glasgow the following May. This summer United have spent £50m already and are still busy. This is about something far bigger than a 20th title.

The sense that an overhaul lay ahead began afflicting Ferguson months ago and certainly long before the Champions League final defeat to Barcelona, which confirmed what he learned through the drab autumn days when his side was struggling at places such as Bolton and Sunderland. It was when he was under the pressure of the Wayne Rooney contract saga last October that Ferguson dropped the pretence and we glimpsed, briefly, in the raw, his feelings that this United side were no longer an immutable force. "Life changes," he said on the day Rooney publicly questioned United. "I don't think one club can win [dominate] for 10 or 15 years. It is impossible for a club to continue that. It was the same situation a few years ago at Chelsea."

March appears to have accentuated an appreciation that 2011 would be 2001 revisited: one last, truly defining summer of business for him. The manager, resigned weeks earlier to losing Edwin van der Sar, had given voice to the mounting gloom he was feeling about Rio Ferdinand playing any further role in the season. It was in early April that Ferguson began pressing Paul Scholes about his plans for the future, just about the time the manager met Soren Lerby, Wesley Sneijder's agent, at United's team hotel before the away match at West Ham. The alarm bells had been ringing about Scholes since early December after he sustained a groin injury at Rangers the previous month. It took seven weeks to heal.

Thus began the groundwork which has seen United set the early running this summer, spending £17m, rising to £20m, for Blackburn Rovers' Phil Jones, £17m on Ashley Young from Aston Villa and £18.9m on Atletico Madrid goalkeeper David de Gea. Jones and De Gea are the easy part. More complex is the challenge of the reshaped midfield and Ferguson's calculations of how to fit everybody in.

Young is generally characterised as a replacement for Ryan Giggs and the player whose arrival gives Luis Nani cause to worry for his future. But that's not how Gérard Houllier saw it at Aston Villa. Houllier discerned as soon as arriving at Villa Park last summer that Young operated better behind the main striker. Asked about Martin O'Neill's perception that Young could potentially be one of the best left-wings in Europe, Houllier replied: "No. He can play on the wing. Whether he can be one of the best in the world in that position... I think he can be one of the best in another position." Last month Fabio Capello agreed that Young is best deployed centrally, "not left-wing or right wing". The growing consensus in football is that Young operates best there.

That would place him in competition with Wayne Rooney, whose partnership operating in the hole behind Javier Hernandez has started delivering such potent results for United and who does not much care to shift left. Nasri offers slightly more variability but he, too, likes to drift in from the right to a central place. The arrival of Sneijder, a classic trequartista, would complicate things yet further. Scholes was certainly exuberant about the idea of him signing this week. "We've been linked to top players, especially Sneijder who has done it in the World Cup as well," he said. Old Trafford's policy is of not laying out cash on players over 26, which offers grounds to believe United's interest in him may be less than is publicised, but Sneijder would create even more of a jam behind the main striker.

Ferguson's track record on signing expensive attacking midfielders at moments like this is certainly not peerless. He certainly got Veron all wrong – and not only because he believed that his signature was "the best things the club has ever done". The Argentine was a deep-lying football quarter-back, pure and simple, doing from a deep-lying position for Lazio what l'architetto Andrea Pirlo did for Milan. Ferguson saw him as an attacking midfielder instead and he bombed.

But Scholes is a believer, where Ferguson is concerned, and has seen the same hunger in the manager he witnessed a decade ago. "His drive and enthusiasm is greater than ever, if anything. It really is bigger than ever," Scholes said. "He will have been thinking about the Barcelona game all summer and working out how he can avoid that sort of thing happening again." Where Ferguson's itch is concerned, expect anything in the weeks to come.

United role: Who can provide the central inspiration in Ferguson's new side?